In order to cost effectively manage OCNs, service providers need trouble-shooting and maintenance tools with visibility at the granularity of individual light paths or wavelengths. Due to the complexity of the optical layer sophisticated optical monitoring was a challenge in OCNs. Hence the need for improved Optical-layer Performance Monitoring (OPM) has been acknowledged, followed by the development of several commercial solutions. While most of these solutions focus on detailed spectral analysis, providing high-resolution wavelength, power and signal to noise ratio measurements, they do not provide any information about the course a particular light path has taken through the network. Network operators spend an inordinate amount of time troubleshooting connectivity problems in their networks. Internet Protocol (IP) networks have extremely useful tools such as IP Traceroute or Link-State Packet (LSP) Traceroute to assist the network operator. IP Traceroute, for example, is a standard tool, on which many network operators rely. Leveraging a known paradigm is easy to use, explain and demonstrate.
Canadian Patent Application Serial No. 2,298,848 to Robinson, Marc C., et al, filed on 15 Feb. 2000 and entitled “Routes and Path Management”, and corresponding U.S. Pat. No. 6,570,867 issued on 27 May 2003 and also entitled “Routes and Paths Management”, describe a cost-effective and efficient framework for management of telecommunications networks. The invention is embodied in a route and path management system that contains a data collector unit for collecting data from individual network elements, a server for processing the collected data into manageable route and path objects and a graphical user interface for a user to manage or monitor routes in an IP network. Most of the prior art, including the above-mentioned patent application, concerns tracing of routes at the IP level and does not address optical light path tracing. Some of these capabilities are available from Network Management Systems (NMS). Use of a commercial off-the-shelf NMS requires the OCN to be compatible with the NMS product. Moreover, it may not be possible to provide a network management port at each node in the OCN because of the increase in cost.
Accordingly, there is a need in the industry for the development of methods and systems for detecting and monitoring light paths of optical signals propagating in optical networks.